Electric furnace



:De'c. 30, 1924.

c. A, BODDlE ELECTRIC FURNACE Filed Sept. l1,- 1920 WITNESSES:

12. Walu INVENTOR Clarence A. Baddz'e ATTORNEY arias-siren A. "17

nonszs ELECT yams.

finalisation filed Scnzemner To all whom if; m 121 conccm Be it know i chat I, CLARENCE l i7l"..

a. citizen of thc United States, end a dent oi'lnfislnirgh, in the county of gheny and oi? lf'cnnsylrann lldf "7 vented a ncw and useful rznproreinm Eleclric Furnaces, of which the following is a specification.

My invention relates to electric Till of the niovahle-elcctrode type and, larly, to eleclrio furnaces of relatively large capacity.

One object of my invention is to onvide an electric furnace of tho nioyable-electrode type that shall have a plurality of so electrodes so connected to a polyohase ply circuit as so prevent doc or:

from one set of electrodes through ti of material acing treated to an adjacent sci: of electrodes. 7

In modern electric-furnace 'pra capacity of the furnace is lliniiied by amount of currentwhich can l ted by the inovahlc electrodes carrying caoacii of the elcci l itcd by the so-called sl' n mic-cl, and currents induced in ad accinv n" are composed oi magnetic material. Moreover, the electrode contact trouhles dcrclop so apidly with increase inthe current as to limit the practical furnace capacifiy.

It has been proposed to operate 2* number of sets of elcctrodesin parallchcircuit rela tion but, in such case, tho electrodes would not evenly divide the local on the ilur In the above case, stabilizing re: is would be necessary and such rcactancc; objectionable.

In a furnace constructed in accordance with my invention, a plnral'y of sins oi halh of electrodes are associated n'ilh on; lllfitelhll contained Within onc he The SBiS oi @lGCLlOQQS connecl'ed i0 onc sup ply circuit in such manner as l flow of current "from one set of elcctrodcs to an adjacent set of elccirodcs. Each electrode of each sci; is operated in any Well known manner in accordance with rh current or the Watts supplied to the fun in accordance with any other electrical. acteristic of the furnace operation.

Although only three sets of elccarodcs have been illustrated in the ring, t is he understood that any desired. or

WESTIN 1 :ennns Zr 1 provided in i 'llustrated, ll con ieclicd hy tr co-phase supp.

"s oi": electrode furnace. in the i ol' eleclrodes or former incaiis to a ch l cuiii. Each set of cs comgn'iscs clear-odes. and the ,ornier meanr three prin'iary mils and nine scco ihree n .(l tollie supply cilcilfeicher in or star relation, as may he desired. set of cleeiroilcs has thrce secondary ings connected to them and such secondary windings are re sectively associated with 'i'he three primary windings The secondary windings cssociaced with each sci of electrodes 11 be connected in delta relation, as or ired" in the accompanying drawii Fig. l a dia rammatic of an electric flirnace constructed in accordance with my inveni'ion.

Fig. 2 diagrammatic view showing nni'n'; of the electrodes.

wing, on electric inrhcarsh 2 and a bath of l wy a threehase sup-- isnig conductors 4i, and of secs of electrodes Y. 8 e to the supcly conduc- 0 ans 6 through a bank of trans formers J). The set of electrodes 7 corn prises QlQZZIOQlJS 11, 12 and 13, she set of clcci'rodcs 8 comprises electrodes 14, 15 and l6, and the set of electrodes 9 comprises eleo irodcs l7 l8 and 19.

' The hanli'. of "lace oriina i second The ouch mated rth arrangement and location of parts may be made within the spirit and scope of my invention, and such modifications are intended to be covered by the appended claims. I

I claim as my invention 2- 1. In an electric furnace, the combination comprising a plurality of sets of electrodes, a three-phase supply circuit, and single transformer means for so connecting said sets of electrodes to the supply circuit as to prevent flow of current from one set of electrodes to an adjacent set of electrodes.

2. In an electric furnace, the combination comprising, a plurality of sets of electrodes, a polyphase supply circuit, and single transformer means for so connecting the sets of i electrodes to the supplycircuit as to prevent flow of current from one set of electrodes to an adjacent set of electrodes.

In an electric furnace, the combination" with a plurality of sets of electrodes, each of said sets comprising three electrodes, and a three-phase supply circuit, of single transformer means forconnccting said sets of 3 electrodes to the supply circuit, said means comprising three primary coils and each of coils.

. with a said sets of electrodes having a secondary coil associated with each of said primary 4. In an electric furnace, the combination plurality of sets of electrodes, and

a polyp ase supply circuit, of single trans- 1 saopoe former means for connecting said sets of electrodes to the supply circuit, said means comprising a plurality of primary coils and each of said sets of electrodes having a secondary coil associated with each of said primary coils.

5. In an electric furnace, the combination with a plurality of sets of electrodes, at single bath of material associated with said electrodes, and a polyphasc supply circuit for supplying energy to the sets of electrodes, of single transformer means for so connecting said sets of electrodes to the supply circuit as to prevent flow of current from .one set of electrodes to an adjacent set of electrodes.

(3. In an electric furnace, the combination with a single hearth containing a bath of material, a. plurality of sets of electrodes associated with said bath, each of said sets comprising three electrodes, and a threephase supply circuit, of transformer means for connecting said sets of electrodes to the supply circuit, said means comprising three primary coils and secondary coils e ual in number to the number of said electro es and so interconnected as to prevent flow of current from one set of electrodes to an adiacent set.

7 In an electric furnace, the combination comprising a plurality of sets of electrodes, a polyphase supply circuit, a transformer means for connecting said sets of electrodes to a supply circuit, said transformer means comprising a lural ity of primary coils and a plurality o secondary'coils respectivel associated with said primary coils and witeach set of electrodes.

In testimony whereof, I have hereunto. subscribed my name this 8th day of September, 1920. a y

CLARENCE A, BODDIE. 

